A group of global experts is proposing a new way of defining and evaluating. obesityreducing emphasis on the controversial body mass index and hoping to better identify those who need treatment for disease caused by excess body fat.
Under the recommendations released Tuesday night, obesity will no longer be defined solely by BMI, height and weight, but by other measurements, such as waist circumference, and evidence of health problems associated with extra pounds. will be done.
It is estimated that obesity affects more than one billion people worldwide. According to the U.S. Centers for Disease Control and Prevention, in the U.S., about 40 percent of adults are obese.
“The whole point of this is to get a more accurate definition so we're targeting people who really need help the most,” said Dr. David Cummings, an obesity expert at the University of Washington and one of its 58 authors. is.” A report published in The Lancet Diabetes and Endocrinology Journal.
The report introduces two new diagnostic categories: clinical obesity and preclinical obesity.
People with clinical obesity meet BMI and other markers of obesity and have evidence of organ, tissue or other problems caused by excess weight. This may include heart disease, high blood pressure, liver or kidney disease, or severe knee or hip pain. These people will be eligible for treatment, including diet and exercise interventions and obesity medications.
People with preclinical obesity are at risk for these conditions, but do not develop the disease, the report said.
BMI has long been considered a poor measure that can over- or under-diagnose obesity, which is currently defined as a BMI of 30 or more. But the report states that people with excess body fat do not always have a BMI greater than 30. And people with more muscle—football players or other athletes—can have a higher BMI despite having normal body fat.
A preliminary analysis shows that under the new criteria, about 20 percent of people who used to be classified as obese will no longer meet that definition. And about 20 percent of people with serious health effects but a low BMI would now be considered clinically obese, experts said.
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“It won't dramatically change the percentage of people who are defined as obese, but it will better diagnose people who really have clinically significant obesity,” Cummings said. “
The new definitions have been endorsed by more than 75 medical organizations worldwide, but it is unclear how widely or quickly they can be adopted in practice. The report acknowledges that implementing the recommendations “will have significant cost and workforce implications.”
A spokeswoman for the health insurance trade group AHIP, formerly known as America's Health Insurance Plans, said it is “too early to predict how plans will incorporate these standards into coverage or other policies.” will.”
There are practical issues to consider, said Dr. Kathryn Saunders, an obesity specialist at Weill Cornell Medicine and co-founder of the obesity treatment company FlyteHealth. Measuring waist circumference seems easy, but protocols vary, many doctors aren't properly trained, and standard medical tape measures aren't large enough for many people with obesity.
In addition, a comprehensive health assessment and laboratory tests will be required to determine the difference between clinical and preclinical obesity.
“For a new classification system to be widely adopted, it also needs to be very fast, cheap and reliable,” he said.
Kate Bauer, a nutritionist at the University of Michigan School of Public Health, said the new definitions are likely to be confusing.
“People like and need simple messages. I don't think that differentiation is going to change anything,” he said.
Dr. Robert Kushner, an obesity expert at Northwestern Feinberg School of Medicine and co-author of the report, acknowledged that changing the definition of obesity will take time.
“This is the first step in the process,” he said. “I think it's a conversation starter.”
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